Chronic rhinosinusitis (CRS) is a common health condition in the United States resulting in more than 200,000 surgical procedures annually, which are not uniformly successful. In this proposal, we present a newer model for understanding CRS surgical outcomes, which we expect will lead to more accurate preoperative prediction of patients likely to benefit from CRS surgery. Our model incorporates a recently developed understanding of the pathophysiology of CRS. The current conceptualization of CRS is one of inflammation with or without anatomic obstruction. Three components play a critical role in CRS pathology 1. Inflammation 2. Polyps 3. Anatomic obstruction. While these three components are clearly related to the pathophysiology of CRS, the question we address in this proposal is how measures related to these components predict surgical outcome. Several factors have been hypothesized to indicate inflammation, polyps, and/or anatomic obstruction and predict surgical outcome. Factors to be considered include demographic and comorbidity factors and objective testing procedures and quality of life. The use of this model of CRS pathology opens up several analytic avenues for better predicting outcomes of CRS surgery, which are to be tested in this project. The studies proposed are hypothesis testing or hypothesis generating in nature. Specific Aims 1 and 2 address the goal of evaluating preoperative factors that are potentially predictive of surgical outcome and developing a predictive model of surgical outcome. Specific Aim 3 explores novel outcomes of sinus surgery including olfactory function and general health related quality of life. This proposal focuses on patients undergoing surgical intervention for the management of CRS. The findings can potentially be applied to the 200,000 patients annually undergoing sinus surgery and in working toward the long-term goal of developing a comprehensive system for measuring extent of disease so that disease severity and treatment response can be rigorously quantified in the 30 million patients with CRS.